The simplicity of something is the fact that it is not complicated and can be understood or done easily.
clarity , straightforwardness
The apparent simplicity of his plot is deceptive.
他的阴谋貌似简单,却具有欺骗性。
Because of its simplicity, this test could be carried out easily by a family doctor.
由于操作简单,这一测试可轻易地由家庭医生完成。